Sorry if this is stupid but im not an expert on 4 dimensions. I bet this has already been proved wrong but its worth a try...
Black Holes, they are just a singularity, how is this possible in 3 dimensions?
If there was a White hole in the 4th dimension that intersected the 3rd dimension which has a black hole at that point too, is it possible that both exists and all the matter from the 3rd dimension that is going through the black hole is being expelled to the 4th dimension?